1. Field of the Invention
The present invention relates to a display screen changeover technique to quickly and easily perform a changeover of content display on a TV screen.
2. Description of the Related Art
Conventionally, there is a television receiver (hereinafter, referred to as TV) that receives broadcast signals transmitted via radio frequencies by an antenna or the like, and provides to viewing audience a preferred program selected by a tuner by displaying the program on a screen. A conventional TV displays a screen according to a format specified by a standard definition television (SDTV) or a format specified by a high definition television (HDTV). Here, the aspect ratio used in SDTV is different from the aspect ratio used in HDTV. Japanese Laid-Open Patent Applications No. 2004-186803 and No. 2007-60676 discloses a technique to convert a program according to an aspect ratio contained in broadcast signals into a program according to a previously set aspect ratio used in a display screen, and display the converted program on a display screen.
In recent years, in order to provide to viewing audience various kinds of information such as program related information, whether information, news information, etc., together with broadcast programs, there is provided data broadcast service such as cable television broadcast, digital broadcast, Internet protocol (IP) broadcast, etc. In this case, for example, signals sent from the above-mentioned various kinds of broadcast are converted into viewable data to be displayed on a TV screen. It should be noted that STB is provided with functions of demodulating or decoding each broadcast data, cancelling scramble, controlling limited reception, displaying electronic program guide (EPG), etc.
Furthermore, the conventional STB has a function of displaying on a TV screen a hyper text markup language (HTML) content such as a Web page (HTML page) acquired from an external server through, for example, the Internet.
According to the service using HTML contents, such as a HTML page supposing TV display, the aspect ratio of the HTML page is set to 4:3 (SD) or 16:9 (HD) so that HTML page can be displayed without scrolling by the display terminal.
It is usual for the service to display HTML pages on a TV to fix the size of the HTML page to an SD size or an HD size. Therefore, the display terminal merely has one browser display corresponding to either the SD size or the HD size.
However, in the service using both the HTML page of HD size and the HTML page of SD size, if a display is made with the fixed browser size, various problems may occur. For example, if an HTML page of SD size is displayed on the browser of HD size, the HTML page is displayed by left-aligned. Additionally, if a browser of HD size is displayed on 4:3 TV, it becomes a letter box display.
Because the HTML page of SD size is displayed in this letter box display, the HTML page displayed becomes small with respect to an area displayed by the TV. Moreover, if an HTML page of HD size is displayed on the browser of SD size, the entire HTML page does not fall within a display area of the browser, and it is necessary to scroll the screen when viewing the HTML page.
With such a service, it is assumed that a general HTML page is used other than that specified in the service. However, in a general site, because a page structure is not set in consideration with TV's over-scanning, the browser display may run off a TV display frame, which may result in that a part of the page cannot be displayed. Accordingly, in many cases, even if it is over-scanned on the TV side, a display is made by scaling the size to be smaller than an actual size so that the entire page can be displayed.
Moreover, when displaying on a TV screen, a display according to a format which a contents provider side desires to display cannot be displayed because the display is made in a state where a user previously sets by STB or the like.